Punch press



Sept. 3, 1940. F. E. MuNsCHAUl-:R ET Al. v 2,213,451

PUNCH PRESS Filed Oct. 30, 1959 3 Sheets-Sheet l si .fa 14' 75 75 /7 ,Z479 60 4/ 5.745 17 36 5/ v 52 52 a m 55 n I# g: al: l-f ,L7/'- HI l: :yil 7@A 59 U 35 v 5; 66 6" --l\`-/l ATTORN EYS Sept. 3, l940 F. E.MuNscHAUER Er AL PUNCH PRESS 3 Sheets-Sheet 2 Filed Oct. 30, 1939 ENToRINV U Sept. 3, 1940.

PUNCH PRESS Filed Oct. 30, 1939 3v Sheets-Sheet 3 F. E. MuNscHAuER E-rAL 2,213,451A

Patented Sept. 3, 1940 rUNcH PRESS y Frederick E. Munschauer and GeorgeE. Munschauer, Buffalo, N. Y., assignors to Niagara Machine and IlFoolWorks, Buffalo, N. Y.

Application October 30, 1939, Serial No. 301,965

15 Claims.

mission means and other movable elements ordi narily associated withpresses of this class. The novel punch press of our invention has aframe element for performing functions corresponding to those of pressframes in the prior art but we have so arranged the component stressmembers of this element as to materially increase the structuralefficiency ofthe frame element and consequently of the punch press withwhich it is associated. f

In our present invention the stress members of the punch press frame areso shaped and arranged that the external loads and forces which may beapplied within safe practical limits of deflection and internal stressof the frame element are very much higher than is the case with pressframes of prior art presses of comparable size,

weight and die capacity. The structural effiay ciency of the punch pressframe which forms a part of our invention is in large part attributableto the novel arrangement of transmission means from the point wherekinetic energy is delivered to the press to the actual point ofapplication in the reciprocation or manipulation of a punch or die orthe like.

The novel arrangement of transmission means alluded to effect theoperation of our punch press First, it permits the beneficially in twoways. highly eicient arrangement of structural elements of the punchpress frame, as set forth above; and second, it results in theapplication of external loads to the press frame in such manner as tominimize their resultant moments. It is to be borne in mind of coursethat allv of the external forces applied to the press frame are throughthe medium of the several elements of the transmission means, using thatterm in its broadest significance, and usually at points on the pressframe where the elements of the transmission means have bearing.

A further substantial advantage in the punch press constructions hereindisclosed resides in the greatly increased safety which results from.designs which present a minimum of exposed moving parts.` sion elementssave the driving pulley, which may be associated with a driving motor ora line shaft, and the actual die supporting slide itself, are completelyhoused and protected, both from themselves doing harm and from beingharmed or impaired by outside agencies.

An advantage which accompanies such housing of` the transmission meansresides in the fact that adequate lubrication of the several movingparts may be conveniently and readily effectedV and' special arrangementof the transmission means in the structural frame element is pro-Substantially all of the transmis-y vided for the purpose of stillfurtherv facilitating 4 and insuring the provision of adequatelubrication of all parts which are sub-ject to wear.

'In the provision of a punch press possessing the advantages anddesirabilities recited in the foregoing, numerous problems havev beenencountered in previous attempts to achieve the objects of the presentinvention. In our improved punch press, exemplary embodiments of whichare shown in the accompanying drawings and described in the ensuingspecification, these problems have been disposed of in a manner whichreconciles the frequently conflicting in-l terests' of facility andeconomy of manufacture, convenience in use, long machine life, and theutmost in vsafety both to the machine itself and to the operator oroperators.

In the drawings: i Fig. 1 is a vertical .cross sectional sideelevational view of one form of the machine of our invention; l i

Fig. 2 is a'front elevational view thereof with portions of the upperpart of the machine frame broken away; y

Fig. 3 is a fragmentary cross sectional view taken on the line III-IIIof Fig. l and showing the crank shaft detent mechanism in detail;

Fig. 4 is a fragmentary sectional viewsimilar to Fig. 1 but showing theupper portion only of a modified form of the invention; and i Fig. 5 isa fragmentary rear elevational view of a casing mountingl portion of themachine of Fig. 4. u g

In the drawings like characters of reference denote like parts and thenumeral l@ designates soA1 generallythe main frame member of the punchrear portion of the bed II. The spaced columns are for the purpose ofsupporting a superstruc- .ture which carries the principal moving partsof the punch press and which is of novel conformation and arrangement inthe present invention.

The form of the columns I2 andl I3 and the manner of their associationwith the bed II is not directly a part of the inventive concept embodiedin the punch press set forth in this application and it is to beunderstood that the details of the machine in this particular may bevaried to satisfy various considerations of design and use. In the formillustrated the columns I2 and I3 are of hollow rectangular crosssection with their depths or major cross sectional axes extendingrearwardly from the rear edge of the bed II. The columns I2 and I3 are,as illus,- trated in Fig. 1, curved forwardly-'at their lower portionsso that they come up beneath and merge with the bed II and support thelatter. The spaced column arrangement is desirable because it permitswork pieces and scrap to be passed therebetween, usually after the workpiece or scrap has been operated upon by a die supported upon the bed II and has passedtherethrough.

The columns I2 and I3 support, at their upper ends, a casing portion I5and the interior of the casing portion I5 has a partition I6 whichdivides the casing into upper and lower chambers. The upper chamber,designated Il, is arranged to house transmission means for operation ofthe press in a manner which will hereinafter appear and the partition I6serves the added purpose of `reinforcing and stiffening the upperportion of the frame I0. l

Various means for supporting the frame I0 upon a suitable foundation maybe employed. If, as is frequently the case in presses of the class underconsideration, it be desired that the press be inclinable to and from anerect or vertical position the supports 20 andy 2l illustrated in thedrawings may be provided. In such case pivot means connect the mainframe Ill and the supports 20 and 2| at a point beneath the bed I I ofthe press. Such pivot means may comprise a pair of axially aligned pivotpins 22 and 23' which pass through the supports 2l) and 2I,respectively, and are secured in the forwardly extending portions of thecolumns I2 and I3.

Mechanism for moving the frame IB about the pivot pins 2E and 23 from avertical position to various rearwardly inclined positions isconventionally provided and it is not believed necessary to anunderstanding ofthe principles of the present invention that such meansbe illustrated. One form of press inclining means may be found inLetters Patent to Frederick Orton, Numbered 2,106,917 and dated February1, 1938. For relatively bracing the main frame I0 and the supports 2Uand 2i with respect to each other arcuate slots 2li struck from vthepivot pins 22 andv23 are formed in the supports 2i! and 2|. A nut andbolt'assembly 28? is associated with each of the slots 2li and analigned opening formed in the lower portion of each of columns I2 andI3. r

At the outside of the front face of the casing portion I5, and usuallyadjacent the lower portion thereof, there is provided a pair ofintegrally formed and laterally spaced projections 21 and 2B forreceiving a pair of adjustab-ly and removably associated gibs .2&3 and39 which are adapted to retain and guide a slide member or ram 3l forvertical reciprocation aga-inst the front of the casing l5. The slidemember 3| is provided with suitable means for securely engaging theupper or movable element of a die. rIhe adjustable and removable gibconstruction and the details of the slide are conventional and wellknown and since such details do not directly and specically form a partof the present invento be supported jointly in the front wall of thecasing I5 and in a portion of the projection 34.

The projection 313 comprises a hollow casing having a top wall Si?, sidewalls St and llt, a front wall fil, and a bottom wall d2. The rear wallof the hollow casing which comprises the projection 34 is identical withan upper portion 154 of the front wall of the casing I5. rhe bottom walli2 of the projection 35 is provided with an approximately centralupwardly directed formation 4@ which provides a recess Il in suchbottorn wall adapted to receive and provide clearance for the crankportion of a crank shaft. The Ywalls of the upward formation @6 arespaced at all points from the interior of the top, side, front and rearwalls which form the outer casing of the projection 34 so that,considering the projection 31% as a cantilever beam with upward bendingloads occasioned by the forces against the crank shaft,` spaced butrigidly constrained tension and compression members are provided.`

While the various portions of the frame have been shown as substantiallyclosed hollow box sections, it will be clear that suitable provisionmust be made for supporting and removing cores in the course of castingthe frame. This is preierably accomplished by locating core prints atpoints which coincide with relatively little stressed portions of theframe structure, such portions lying close to the neutral nbre of theframe, considering the various cross sections thereof as beam sections.ri'he holes left by the core prints may, after removal of the cores, bepermanently closed by welding plates in or over the openings, whichwould be the case in the press illustrated in the drawings, or the holesmay be closed by removable plates or even left open. In any event thedisposition of the holes is such as not to materially lessen thestrength of Lthe frame.

Adjacent the bottom of the projection 34 and at opposite sides of `therecess lll, front and rear,

`are the bearings iid'and 36, respectively, previously referred to. Itwill be noted from an inspection of Fig. l that each of the bearings 35and 36 is of substantial length and is supported and directly backed ateach of its ends by either an inner or an outer wallportion of theprojection 34. It will further be noted that each such backing wallportion extends directly vertically to the point where it merges withone of the spaced -top wall portions and the structural eiiciency of thearrangement and disposition of these elements and the rigidity therebyafforded will be apparent.

The front bearing 35 includes a cylindrical bearing block 50 which isremovably associated with the lower forward portion of the projection34. This end may be accomplished by providing an arcuate or circularopening or recess in the projection 34. The cylindrical bearing blockmay conveniently be held against accidental removal by screws 52 whichpass through an annular flange 53 formed on the cylindrical bearingblock and engage in the projection 34. This construction of the frontbearing 35 permits ready removal or assembly of the bearing block in theprocess of erecting or dismantling a punch press.

A crank shaft 55 for effecting reciprocation of the slide 3l has journalportions 5l and 58 which are supported in the b-earings 35 and 35,respectively, and intermediate such journal portions the crank shaft isprovided with a .crank 59, the crank pin of which engages rotatably withone end of a connecting member or pitman 58.

The other end of the connecting member 50 is engaged with the slide 3lby means of a ball and socket joint designated generally 8l and whichpermits the connecting member E0 to incline freely with respect to theslide 3l as the opposite end of the connecting member is caused torevolve with the crank pin.

The details of the connecting member and of its connection with thecrank 59 and the slide Si, respectively, are not new excepting in thatthe plane of rotation of the crank 55 is at right angles to the usualplane of rotation of cranks in presses of the general class comprehendedin the present invention and consequently the axis of the crank shaftruns from front to rear of the machine generally and of the slide inparticular.

Referring now to the means for rotating the v crank shaft 55 and forcontrolling its rotation, special attention is directed to Fig. l wherethe crank shaft is shown extending rearwardly into the interior of thecasing portion l5 for engagement with and by suitable transmission meanswhich are arranged and disposed in a novel manner. In addition to thebearings 35 and 36 the crank shaft is provided with a rear bearing 63formed in a removable cover member 65 which is disposed over an openingprovided in the rear wall of the casing l5. For smoother and more nearlyfrictionless operation a ball bearing 55 or the like may be provided inassociation with the bearings 63 and the rear journal portion of thecrank shaft 55.

A ywheel 66 is rotatably disposed on the crank shaft intermediate thebearings 36 and 63 and the flywheel may have gear teeth formed thereon,as in the illustrated embodiment, and thereby constitute an element inthe means for transmitting rotary motion to the crank shaft 55. Theflywheel is supported for rotation on the crank shaft 55 by means of apair of ball bearings 58 and E9 and the right hand ball bearing 59, asviewed in Fig. l is held against axial displacement by reason of theprovision, at its left side, of a collar or sleeve 'I8 which is disposedabout the crank shaft 55 and between the ball bearing 59 and a shoulderformed by a reduction in diameter of the crank shaft 55.

At its other side the ball bearing 59 is in abutment with the hub of acam 1| which is provided for a purpose which will hereinafter appear andthe hub of the cam extends to the ball bearingv 55 which mounts the rearend of the crank shaft 55. The ball bearing 55 is held against axialdisplacement by a nut i2 which engages the threaded end of the shaft 55and urges the bearing 55 against another shoulder formed by a stillfurther reduction in the diameter of the crank shaft 55 at this point.

A countershaft 'l5 is provided for imparting rotative motion to thecrank shaft 55 through engagement between a pinion 16 carried by thecountershaft l5 and the gear teeth formed on the flywheel 65. Theflywheel is adapted to be selectively and intermittently connected tothe crank shaft 55 for transmitting its rotative movement to the latterin a manner which will presently appear. The countershaft 'I5 issupported by means of bearings 'i8 and 19 which may be formed integrallywith the frame member il] and the latter of which is associated with therear wall of the casing portion l5 of the frame member.

Ball bearings are preferably provided in conjunction with the bearings18 and 'I9 for more efficient operation as indicated in Fig. 1 of thedrawings. It will be noted that in the illustrated embodiment a portionof the countershaft projects rearwardly through rear bearing 19 andthrough a cap which is provided for the purpose of retaining the ballbearing and consequently the countershaft itself in propery axialposition.

This rearward projection of the countershaft 'l5 is provided for thepurpose of supporting a drive pulley 8| which may be connected withmeans for imparting rotative movement thereto by belts 82. Such motivemeans may constitute a line shaft or, as in the illustrated instance, anindividual motor drive including an electric motor 83 disposed at theoutside of the frame of the press l0 vand secured thereto by a pivot 84and a screw connection 85, Vthe latter being adjustable to regulate thetension of the belts 82.

From the previous description it will be apparent that the flywheel 55is mounted for normally free rotation with respect to the crank shaft55, but suitable mechanism is provided for selectively establishingdriving engagement between the flywheel-and the crank shaft. Suchmechanism is provided, in the illustrated embodiment, in the form of ajaw clutch which is similar in form and arrangement tov clutches wellknown in the art, save with respect to its arrangement and dispositionwith relation to the remaining elements of the present new combination.

One clutch element 88 is secured against the flywheel 56 as by thescrews or studs 89 and has on its outer radial face spaced radiallyextending clutch teeth for cooperation with the teeth of a complementaryclutch element 9U. The latter element is slidable axially with respectto the crank shaft 55 but has a spline or feather key connectiontherewith for causing joint rotation of the clutch element 90 and thecrank shaft. A conventional spring, which does not appear in thedrawings, is provided for normally urging the clutch element 9i! intoclutching engagement with the clutch 89. With the clutch p-arts in theposition illustrated in Fig. 1 the clutch elements 89 and 98 arerelatively disengaged by virtue of the engagement of a clutch pin 92with at camming shoulder 93 formed on the clutch element The clutchmechanism is of the single revolution type and the pin 92 is connectedin a conventional manner with manual operating means for withdrawing thepin radially away from the clutch element Si) and out of engagement withthe shoulder 93 against the resistance of a spring which tends to urgethe pin toward the axis of the clutch element. When the pin 92 ismomentarily withdrawn from its engagement with the shoulder 93 byoperation of the,- manual means the clutch element 90 is moved intoengagement with the clutch element 89 and joint revolution of theflywheel and the crank shaft ensues.

If the manualoperating means is released before a predetermined portionof a single revolution is completed the pin 92 is moved, by means of thespring previously referred to, toward the axis of the crank shaft and tothe position it occupies in Fig. 1, whereupon subsequent rotation of theclutch element 90 brings the shoulder 93 and the pin 92 into cammingengagement and the clutch element 90 is cammed axially to the left andout of clutching engagement with the element 89, the position in whichthe parts are shown in Fig. 1.

The stopping of the crank shaft in a predetermined angular position uponinterruption of clutching engagement is assured b-y means which will nowbe described. Having reference particularly to Fig. 3, the cam '|Ipreviously mentioned is xed to the crank shaft E5 by a key connection. Acam follower or roller 95 is rotatably supported by one end of a lever96 whose opposite end engages about a spring pin 91 and the lever 9B ispivotally secured to a portion of the stationary frame member of thepunch press intermediate its ends and by means of a pivot pin 98.

The spring pin 97 also has pivotal support against the frame member asby means of the pivot pin 99 and the pivot pins 98 and 99 mayconveniently be associated with the rear wall of the casing portion l5of the frame of the press. The engagement of the end of the lever 96about the spring pin 9T is such as to permit pivotal movement of thelever about its fulcrum and a coil spring it surrounds the pin 91 belowthe lever St. The coil spring |09 is compressed between the under sideof the end of the lever 96 and a nut lill by means of which the initialtension or" the spring may be selectively adjusted. A locking nut |02 isalso preferably provided.

The cam means thus provided is arranged to cooperate with the clutchingmeans to effect stopping of the crank shaft and the parts driven therebyin a predetermined phase of their cycle of movement and at the same timeserve to modify the distribution of the several loads throughout theoperating cycle so that the available torque may be more eflicientlyapplied and utilized. To this end the cam` 'H is formed so that itsoutline is generally that of an eccentric circle with a lower andsomewhat more abrupt inwardly curving portion at the point where theeccentric outline most nearly approaches the axis of rotation of thecam. In actual practice the general outline of the cam 1| is not trulythat of an eccentric circle but the contour may be so classified herefor the purpose of describing its relation to the present invention.

In the illustration of Fig. 3 the cam follower 95 is shown in engagementwith thie latter inwardly curving portion and as the -several partsapproach the illustrated position toward the conclusion of a cycle ofrotation, and with the clutch already disengaged, a resilient butsufliciently positive tendency to detain the cam and its related partsin the position illustrated is exerted by reason of the spring |60.

Apart from this local tendency of the cam to be retained in apredetermined position with the follower disposed in engagment with theinwardly curving portion, the general e'ccentricity of the cam outlineis such that during approximately half of the revolution of the crankshaft the follower is moved away from the axis of the cam and throughthe medium of the lever 96 the spring is compressed by such movement ina manner which will be clear from an inspection of Fig. 3. This loadingof the spring IBB is arranged to takeA place when the crank of the crankshaft, the slide, the connection between the crank and the slide, andthe punch secured to the slide, are all moving downward and the springloading thus tends to absorb and neutralize the kinetic energy releasedby those elements in their downward movement. Conversely, the remainingportion of the cam outline is such that the cam follower has a returnmovement toward the axis of the cam during which time the spring |00 isunloaded and the kinetic energy previously stored in the spring servesto assist in lifting the weight of the parts previously recited as theyare moved upwardly.

Referring to Fig. 1, it will be noted that the partition i6 which formsthe bottom wall of the chamber Il which houses the transmission means isformed to provide a sump adjacent the lower portion of the flywheel gear5% whereby the moving parts of the transmission means may be adequatelylubricated by filling such sump to a suflicient level so that the lowerportion of the flywheel runs in the lubricant. Lubricant entrained bythe flywheel is lifted and a portion thereof iiows over the closelyadjacent clutch mechanism at one side of the flywheel and the detent andcounterbalance mechanism at the other side of the flywheel. A slightlyinclined groove |86 is formed in the bottom wall of the sump |95 andleads to a drain plug lill at one side of the frame of the press, as maybe seen from Fig. 2, for the purpose of draining the sump |55 whendesired.

Reference will now be had to the modified form of press illustrated inFigs. 4 and 5 and to avoid needless repetition, the modification ofFigs. 4 and 5 will be discussed with 'reference to the manner in whichit differs from the construction of Figs. 1, 2 and 3, it beingunderstoodl that all details not specically mentioned are to be asnearly the same as corresponding details in the iirst-describedembodiment as conditions permit. Speaking generally, the maindistinguishing feature of the embodiment of Figs. 4 and 5 resides in thefact that a separate casing portion |39 is provided for housing theportion of the transmission means which acts between and serves toconnect the drive pulley i3! with the crank shaft |32. Certainadvantages are secured by thus providing a transmission housing which isformed separate from the main frame of the press, which in Figs. 4 and 5is designated generally |33. By forming the casing portion |36separately the machining of the several bearings and other finishedsurfaces thereof is substantially facilitated since those operations canin that way be accomplished on a smaller machine than if such casingportion were formed integrally with the main frame of the machine as inthe embodiments of Figs. 1 through 3. From the standpoint of economy ofproduction this is an important consideration and the attainment of thegeneral objects of the present invention by using a separatetransmission housing for cooperation with the main frame of the machinerepresents a highly satisfactory alternative mode of carrying out theprinciples of the invention which form the subject of this application.

75; connection with the slide to reciprocate the f With furtherreference to Fig. 4, a pulley shaft 35 is journaled in the casing E38,one bearing therefor being disposed in the rear wall of the casing 'itiland another being provided inside the casing and preferably formedintegrally therewith as at E36, A pinion l3ll onthe pulley shaft 35meshes with a gear i738 which is rotatably disposed upon the crank shaft13G. For effecting rotation of the crank shaft with the gear i3d, clutchmechanism indicated generally at ifi-i3 is provided. Since such clutchmechanism may be the same as that illustrated in connection with theinst-described modication no further description thereof is necessary,save to state that the stationary portions there of are secured to thefront wall of the. casing member i3@ and securing screws therefor areindicated at lill in Fig. 5, which is a cross sectional view looking atthe inside of the front wall of the casing member i3@ from the rear ofthe machine.

Counterbalancing and detent mechanism is associated with the rear end ofthe crank shaft 132 as in the previously described embodiment, and suchmechanism is indicated by the numeral |132 in Fig. 5. v l

The main portion of the press frame |33 is formed similarly to the pressframe lli of Figs. 1 through 3 with the exception of the fact that upperrear portion for housing the transmission means is omitted and whatconstituted the partition dfi or the previous embodiment is, in thepresent modification, the rear Wall lll/3 of the press frame. Such rearwall M4 is located a greater distance back from the crank of the crankshaft than in the former case to give ample strength to the frame and toaiford, at this point, a beam of'ample depth for resisting and absorbingthe bending moments which are applied to the press frame in this region.Such greater' depth of the frame H33 at this'point dictates the use of alonger medial bearing M5 for the crankshaft which actually results in avery rigid and vibrationless crank shaft and bearing construction. l f

The transmission casing I3@ is provided with a sumpportion M6 forcontaining a lubricant supply for Vthe same purpose as in theconstruction of Figs. l through 3. The rear wall ldli of the framemember E33 and the front wall of the casing machined pads Ml and M8respectively and screws M9, see Fig. 5, serve to keep thesevpads inabutment and the frame 33 and the casing |31) in assembled relation.

While specific embodiments of' the principles of our invention have beenshown in the draw-` ings and described herein, it is to be understoodthat the invention is not limited thereto or otherwise than as definedin the appendedl claims.

We claim:

1. In a punch press, a frame member comward extension at its front walland above said` slide, a bearing element provided at the forward portionof said extension and an aligned bearing element spaced rearwardly ofthe rst'bea'ring element, a crank shaft `iournaled in saidy bearings andhaving a crank therebetween for i3@ are provided with complementarylatter, said crank shaft having a portion thereof extending rearwardlyinto the vinterior ofv the hollow casing portion, bearing meansassociated with said frame member for supporting the rear terminalportion of the crank shaft, a countershaft journaled in said casingportion, a flywheel on said crank shaft within said casing portion andmeans for transmitting rotary motion from ing bed disposed below saidslide and a forward extension at its front wall and above said slide, acrank shaft journaled in said forward extension and extending rearwardlyinto theinterior of said casing portion, said crank shaft having a crankfor connection with the slide to reciprocate the latter, bearing meansassociated with said frame member for supporting the rear terminalportion of the crank shaft, a flywheel rotatably mounted upon said crankshaft between said forward extension and saidY bearing means and withinsaidv casing portion, a clutch element secured tosaid ywheel' and acooperating clutch element fixed for rotation with said crank shaft andmovable axially to and from engagement with said rst clutch element, `acam fixed for rotation with said crankshaft and disposed adjacent saidflywheel, and a follower and resilient means for urging said followeragainst said cam, said cam being arranged in timed relation with respectto said clutch elementsk and having rises and falls ar, ranged to loadand unload said resilient means as the several bodily moving elements ofthe punch press move downwardly and upwardly respectively tocounterbalance said bodily moving elements. v

3. In a punch press, a frame member comprising a hollow casing portion,a reciprocable slide and means at lthe outside of the front wall of thecasing portion for supporting and guiding the same, said frame memberhaving a die-receiving bed disposed below said slide and a forwardextensionat its front wall and above said slide, a crank shaft journaledin said forward extension and extending rearwardly into the interior ofsaid casing portion, said crank shaft having a crank for connection withsaid slide to reciprocate the latter, bearing means associated with saidframe member for supporting the rear terminal portion of the crankshaft, a flywheel rotatably mounted upon said crank shaft intermediatesaid forward extension and said bearing means and within said casingportion, a clutch element secured to the forward face of said flywheeland a cooperating clutch element i'lxed for rotation with said crankshaft and movable axially to and from clutching engagement with said rstclutch ele-3 ment, a cam xed for rotation with said crankshaft anddisposed thereon rearwardly of said flywheel, a follower for said cam,and resilient means supported 'upon the rear wall of said'casing portionand acting between said stationary casing portion and said follower tourge the latter` into engagement with the cam vpath of said cam, saidcam being arranged in tirned relation with respect to said clutchelements and having rises andfalls arranged to load and unload saidresilient means as the slide and a movable portion 75 BOL of a dienormally carried thereby move downwardly and upwardly respectively tocounterbalof the casing portion for supporting and guiding the same,said frame member having a die-receiv ing bed disposed below said slideand a forward extension at its front wall and abo-ve said slide, a crankshaft journaled in said forward extension and extending rearwardly intothe interior of said casing portion, said crank shaft having a crank forconnection with said slide to reciprocate the latter, bearing meansassociated with said frame member for supporting the rear terminalportion of the crank shaft, a flywheel rotatably mounted upon said crankshaft intermediate said forward extension and said bearing means andwithin said casing portion, a clutch element secured to the forward faceof said flywheel and a cooperating clutch element xed for rotation withsaid crank shaft and movable axially to and from clutching engagementwith said first clutch element, a cam fixed for rotation with said crankshaft and disposed thereon rearwardly of said iiywheel, a follower forsaid cam, and resilient means supported upon the rear wall of saidcasing portion and acting between said stationary casing portion andsaid follower to urge the latter intoengagement with the cam path ofsaid cam, said cam being arranged in timed relation with respect to saidclutch elements and having rises and falls arranged to load and unloadsaid resilient means as the slide and a movable portion of a dienormally carried thereby move downwardly and upwardly respectively tocounterbalance said do-Wnwardly and upwardly moving elements, said camhaving in its outline a detent depression whereby the cam follower,under the urge of the resilient means, is adapted to ride into saiddepression after said clutch elements have been disengaged vtoaccurately determine the angular relation of the crank shaft at the endof an operating cycle.

5. In a punch press, a frame member comprising a hollow casing portion,`a reciprocable slide and means at the outside of the front wall of thecasing portion for supporting and guiding the same, said frame memberhaving a die-receiving bed disposed below said slide, a crank shaftjournaled in the front and rear walls of said hollow casing portion andhaving a crank outside Of said casing at the front thereof forconnection with said slide to reciprocate the same, a flywheel disposedupon said crank shaft within said hollow casing portion and means withinsaid casing' portion and associated with said crank shaft forcontrolling the rotation thereof, said hollow casing portion having abottom wall and a sump formed in said bottom wall and disposed about alower portion of said flywheel, whereby rotation of said iiywheelentrains lubricant provided in said sump for lubrication of the rotationcontrolling means.

6. In a punch press, a frame member comprising a hollow casing portion,a reciprocable slide and means at the outside of the front wall of thecasing portion for supporting and guiding the same, said frame memberhaving a die-receiving bed disposed below said slide, a crank shaftjournaled in the front and rear walls of said hollow casing portion andhaving a crank outside of said casing at the front thereof forconnection vwith said slide to reciprocate the same, a iiywheel lcasingportion having a bottom wall and a sump formed in said bottom wall anddisposed about a lower portion of said flywheel, 'whereby rotation ofsaid flywheel entrains lubricant provided in said sump for lubricationof the rotation controlling means, said hollow casing portion beingsealed against egress of the lubricant contained and circulatingtherein.

7. In a punch press, a frame member comprising a hollow casing portion,a reciprocable slide and means at the outside of the front wall of thecasing portion for supporting and guiding the same, said frame memberhaving a die-receiving bed disposed below said slide, a crank shaftjourrnaled in the front and rear walls of said hollow casing portion andhaving a crank outside of said casing at the front thereof forconnection With said slide to reciprocate the same, a flywheel disposedupon said crank shaft within said hollow casing portion, and meanswithin said casing portion and associated with said crank shaft forcontrolling the rotation thereof, said means comprising a positivemechanical clutch for effecting driving connection and disconnectionbetween said iiywheel and said crank shaft and mechanical detent meanssynchronized therewith and operative to resiliently arrest movement ofsaid crank shaft after disconnection is effected b-y said clutch and ata predetermined phase of its angular cycle of movement.

8. In a punch press, a frame member comprising a hollow casing portion,areciprocable slide and means at the outside of the front wall of thecasing portion for supporting and guiding the same, said frame memberhaving a die-receiving bed disposedbelow said slide, a crank shaftjournaled in the front and rear walls of said hollow casing portion andhaving a crank outside of said casing at the front thereof forconnection with said slide to reciprocate the same, a flywheel disposedupon said crank shaft within said hollow' casing portion and meanswithin said casing portion and associated with said crank shaft forcontrolling the rotation thereof, said means comprising a positivemechanical clutch for effecting driving connection and disconnectionbetween said flywheel and said crank shaft and mechani- Cal detent meanssynchronized therewith and operative to resiliently arrest movement ofsaid crank shaft after disconnection is effected by said clutch and at apredetermined phase in its angular cycle of movement, said casingportion having a bottom wall, and a sump formed in said bottom Wall anddisposed about a lower portion of said flywheel, whereby rotation ofsaid flywheel entrains lubricant provided in said sump for lubricationof the rotation controlling means.

9. In a punch press, a frame member compris-l ing a hollow casingportion, a reciprocable slide and means at the outside of the front wallof the casing portion for supporting and guiding the same, said framemember having a die-receiving bed disposed below said slide, a crankshaft journaled-in the front and rear walls of said hollow casingportion and having a crank outside of said casing at the front thereoffor connection with said slide to reciprocate the same, a ywheeldisposed upon said crank shaft within said hollow casing portion andmeansI within said casing portion and associated with said crank shaftfor controlling the rotation thereof, said means comprising a positivemechanical clutch for effecting driving connection and disconnectionbetween said flywheel and said crank shaft and disposed adjacent saidflywheel at one side thereof, said means also comprising mechanicaldetent means synchronized with said clutch and disposed adjacent saidflywheel at the opposite side thereof for resiliently arresting movementof said crank shaft after disconnection of said clutch is effected andat a predetermined phase in the angular cycle of movement of said crankshaft, said casing portion having a bottom wall, and a sump formed insaid bottom wall and disposed about a lower portion of said flywheel,whereby rotation of said flywheel entrains lubricant provided in saidsump for lubrication of the clutch and detent means lying on oppositesides of said flywheel 10. In a punch press, a frame member comprising ahollow casing portion, a reciprocable slide and means at the outside ofthe front wall of the casing portion for supporting and guiding thelsame, said frame member having a die-receiving bed disposed below saidslide, a crank shaft journaled in the front and rear walls of saidhollow casing portion and having a crank outside of said casing at thefront thereof for connection with said slide to reciprocate the same, aflywheel disposed upon said crank shaft within said hollow casingportion, and means within said casing portion and associated with saidcrank shaft for controlling the rotation thereof, said means comprisinga positive mechanical clutch for effecting driving connection anddisconnection between said flywheel and said crank shaft and disposedadjacent said flywheel at one side thereof, said means also comprisingmechanical detent means synchronized with said clutch and disposedadjacent said ywheel at the opposite side thereof for resilientlyarresting movement of said crank shaft after disconnection of saidclutch is effected and at a predetermined phase in the angular cycle ofmovement of said crank shaft.

l1. In a punch press, a frame member comprising a hollow casing portion,a reciprocable slide and means at the outside of the front wall of thecasing portion for supporting and guiding the same, said frame memberhaving a die-receiving bed disposed below said slide, a crank shaftjournaled in the front and rear walls of said hollow casing portion andhaving a crank outside of said casing at the front thereof forconnection with said slide to reciprocate the same, a flywheel disposedupon said crank shaft within said hollow casing portion, and meanswithin said casing portion and associated with said crank shaft forcontrolling the rotation thereof, said means comprising a positivemechanical clutch disposed forwardly of said flywheel for effectingdriving connection and disconnection between said flywheel and saidcrank shaft, said means also comprising a mechanical detent disposedrearwardly of said ywheel for arresting movement of said crank shaft,said detent including a cam fixed for rotation with said crank shaft andresilient means supported by the rear wall of said casing portion andacting against said cam to resiliently detain said cam and said crankshaft in a predetermined position after clutch disconnection.

l2. In a punch press, frame means including a hollow casing portion, areciprocable slide and means at the outside of the front wall of theframe means for supporting and guiding the same, said frame means havinga die-receiving bed disposed below said slide and a forward eX- tensionat its front wall and above said slide, a

bearing elementprovided at the forward portion of said extension and analigned bearing element spaced rearwardly ofthe first bearing element, acrank shaft journaled in said bearings and having a crank therebetweenfor connection with the slide to reciprocate the latter, said crankshaft having a portion thereof extending rearwardly into the interior ofthe hollow casing portion, bearing means associated with said hollowcasing portion for supporting the rear terminal portion of the crankshaft, a countershaft journaled in said casing portion, a flywheel onsaid crank shaft within said c'asing portion and means for transmittingrotary motion from said countershaft to said flywheel, and meansadjacent said flywheel for selectively engaging and disengaging saidflywheel and said crank shaft fo-r joint and relative rotationrespectively.

13. In a punch press, frame means including a hollow casing portion, areciprocable slide and means at the outside of the front wall of theframe means for supporting and guiding the same, said frame means havinga die-receiving bed disposed below said slide, a crank shaft journaledin said hollow casing portion and having a crank portion disposedforwardly of said casing portion for connection with said slide toreciprocate the same, a fiywheel disposed upon said crank shaft withinsaid casing portion and means within said casing portion and associatedwith said crank shaft for controlling the rotation thereof, said hollowcasing portion having a bottom wall and a sump formed in said bottomwall and disposed about a lower portion of said flywheel, wherebyrotation of said ywheel entrains lubricant provided in said sump forllubrication of the rotation controlling means.

14. In a punch press, frame means including a hollow casing portion, areciproc'able slide and means at the outside of the front wall of theframe means for supporting and guiding the same, said frame means havinga die-receiving bed disposed below said slide, a crank shaft journaledin said hollow casing portion and having a crank portion disposedforwardly of said casing portion for connection with said slide toreciprocate the same, a flywheel disposed upon said crank shaft withinsaid casing portion and means within said casing portion and associatedwith said crank shaft for controlling the rotation thereof, said meanscomprising a positive mechanical clutch for effectingv drivingconnection and disconnection between said flywheel and said crank shaftand mechanical detent means synchronized therewith and operative toresiliently arrest movement of said crank shaft after disconnection iseffected by said clutch and at a predetermined phase of its angularcycle of movement.

l5. In a punch press, a main frame member and a hollow casing portionassociated therewith and disposed to the rear of the upper portion ofsid frame member, a reciprocable slide and means at the outside of thefront wall of the frame member for supporting and guiding the same,Isaid frame member having a die-receiving bed disposed below said slideand a forward eX- tension at its front wall and above said slide, abearing element provided at the forward portion of said extension and analigned bearing element spaced rearwardly ofthe first bearing element, acrank shaft journaled in said bearings and having a crank therebetweenfor connection with the slide to reciprocate the latter, said crankshaft having a portion thereof extending rearwardly into the interior ofthe hollow casing portion, bearing means associated with the rear Wallof the casing portion for supporting the rear ter'- minal portion of thecrank shaft, a countershaft journaled in said casing portion, a flywheelon said crank shaft within said casing portion and means fortransmitting rotary motion from said countershaft to said ywheel, andmeans adjacent said ywheel for selectively engaging said ywheel and saidcrank shaft for joint and relative rotation respectively.

FREDERICK E. MUNSCHAUER. GEORGE E. MUNSCHAUER.

